Biodegradable tea bag. Coloured scanning electron micrograph (SEM) of a biodegradable tea bag. Tea bags are now available made from 100% plant-based material that is fully biodegradable and free from synthetic materials. This will cut down on plastic pollution caused by the UK's favourite hot drink. In Europe at least 60 billion cups of tea are consumed annually and about 96 percent of them are created using tea bags. Polypropylene is a plastic in the tea bags that keep the product together with waste that adds up to over 149,000 kilograms per year. Magnification: x160 when printed at 10cm wide.